How is coal mined?
How is coal mined?
Coal is a productdecomposition of plants. According to some experts, it was formed several hundred million years ago. Its extraction is carried out by various methods, depending on the depth of the deposit in a particular field.
Instructions
1
Open method is used in the extraction of seamscoal, located shallow under the ground (not more than 100 meters). With this method, quarries or coal mines are developed. In production, bulldozers and bucket loaders are used to load material. Coal is exported, as a rule, to dump trucks. At the end of the mining operations, the pit is again filled with layers and recultivation is carried out.
2
Underground mining is carried out with the help offlat wells, on which coal is delivered to the earth's surface. According to the types of development, the galleries (horizontal, deep into the rock) and mine methods are distinguished. Underground methods only high-grade minerals are extracted, because drilling of the mine is very expensive. To date, the deepest mines are not deeper than 2 km below the ground. The oldest method of coal mining is the galleries.
3
After the delivery of coal to the earth's surfacetransported to the factory, where large pieces of material are broken up, and the stones undergo water treatment. After all operations, the rock is loaded into wagons and delivered to enterprises using coal as raw material. Coal is also assigned classes in accordance with the extraction area and its composition. There are gas, fatty, brown, coke and other varieties.
4
For underground excavation, transportation and deliveryCoal to the surface is often used the method of hydraulic extraction through the use of a liquid washing away the coal rocks. To do this, often use the flow of groundwater in the direction of the mine or high-speed directional water jets.
